• Journal of Life Science
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• 제9권1호
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• pp.40-44
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• 1999

Glutathione S-transferase (GST) is a multifunctional protein that catalyzes the catalyzes the conjugation of glutathione with electrophilic compounds. It exists in a variety of isoenzy-matic froms with a wide range of substrate specificity and plays a pivotal role in detoxification of various drugs. In order to elucidate the GST-${\pi}$'s involvement of multidrug resistance (MDR) in drug-resistant tumor cell lines, we determined GST-${\pi}$ content by "1 step sandwich method". Consequently, adriamycin resistant cells of MCF-7 (MCF-7/ADM) have 7-fold increase of GST-${\pi}$ content than that of MCF-7 cells, while its {TEX}$IC_{50}${/TEX} was 116-fold greater than parent cell line. By northrn blotting, we compared whether MCF-7/ADM cells express GST-${\pi}$ mRNA. The GST-${\pi}$ mRNA expression in these cells was not inducible, but constitutive when treated for 24 h with a concentration of 0, 20, 200, and 2000 nM of adriamycin, respectively. Taken together, these results suggest that GST-${\pi}$ may not be directly associated with multidrug resistance in these human cancer cell lines.ell lines.

• 한국환경성돌연변이발암원학회지
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• 제11권2호
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• pp.148-160
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• 1991

인체의 여리 조직을 대상으로하여 면연조직화학전방법을 통하여 glutathione transferase isoenzyme의 분포를 비교 분석하였다. 상피조직중의 GST-Pi의 다랑분포가 확인되었으며, 특히 외인성 화학물질에 노출되기 쉬운 피부, 유두, 신도 등의 과립층과 췌장, 담도, 타액선, 신세뇨관등의 배설관의 상피 또는 난소의 theca와 granulosa, 고환의 Leydig세포, 부신피 질의 zona reticularis 등의 steroid 생합성이 왕성한 부위에서 높은 GST-Pi 분포가 관찰되었다. 면역조직화학적 분석과 병행하여 Western blot 분석을 시행해본 결과 이러한 GST-Pi 분포가 인체유래 유각상피세포 중에서도 확인되었다. 그러나 K-ras 암유전자로 형질전환하여 암화능을 갖춘 인체상피세포주의 GST-Pi 발현은 유의한 차이를 보이지 않았다. 뿐만아니라 타액중에서도 GST-Pi가 다량 존재함이 Western blot 분석에 의하여 구명되었다. 이러한 결과는 GST-Pi가 인체조직 중 외인성독성물질에 노출되는 부위, 내인성 steroid 합성부위 및 배설능을 갖는 부위의 상피조직에 주로 존재하고 있음을 보여주고 있으며, 이러한 GST-Pi의 조직분포는 동효소가 인체의 해독기능에 주요한 역할을 하고 있음을 시사해주고 있다.

• 한국환경성돌연변이발암원학회지
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• 제24권1호
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• pp.19-24
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• 2004

In order to understand the mechanism of the regulation of drug metabolizing enzyme gene expression, we have studied the induction of CYP1A1 and $GST\alpha,$ $\mu,$ $\pi$ enzymes in Japanese monkey and rhesus monkey after the treatment with 3-methylcholanthrene (3MC) and di-n-butyl phthalate (DBP) and bisphenol A (BPA). The levels of mRNA were measured by RT-PCR in brain, intestine and liver. In the case of adult monkey, treatment with 3MC induced CYP1A1 mRNA in intestine by 11-fold. The treatment with DBP induced CYP1A1 mRNA. Effects of 3MC and DBP on GST mRNA expression was not clear. But $GST\mu$ was slightly inhibited by the treatment with 3MC and DBP. $GST\alpha$ was induced in intestine by 1.5-fold. $GST\pi$ was slightly induced by the treatment with 3MC and DBP in intestine. In the case of fetus monkey, the basal levels of fetus CYP1A1 mRNA and GSTs mRNA were relatively low compared to adult monkey. As the age of monkey increased, the basal levels of CYP1A1 mRNA were also increased. 3MC induced the expression of CYP1A1 mRNA didn't significantly induce CYP1A1 mRNA in intestine. The levels of $GST\mu$ and $GST\pi$ were not changed by the treatment with 3MC and DBP. $GST\pi$ was slightly induced by the treatment with 3MC and DBP.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7375-7379
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• 2013

The main aim of this study was to investigate the roles of GST-${\pi}$ and $pol{\beta}$ genes in the chemoresistance of esophageal carcinoma cells. Eukaryotic expression vectors containing each gene were constructed and transfected into EC9706 cells, and the biological effects of the two genes assessed based on a resistance index. We additionally investigated the in vitro and in vivo anti-resistance effects of GST-${\pi}$ and $pol{\beta}$ genes using recombinant lentiviruses carrying siRNAs against the two genes. Our results showed that upregulation of GST-${\pi}$ and $pol{\beta}$ genes suppresses chemosensitivity of esophageal carcinoma cells to cisplatin, while downregulation of these two genes with RNAi technology reverses this chemoresistance. Multi-site injection of recombinant lentivirus targeting the GST-${\pi}$ gene into transplanted cDDP tumors effectively reversed their chemoresistant phenotype. However, the same treatment against the $pol{\beta}$ gene did not lead to significant efficacy against chemoresistance.

• 한국환경성돌연변이발암원학회지
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• 제24권2호
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• pp.73-78
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• 2004

In order to understand the mechanism of the regulation of drug metabolizing enzyme gene expression, we have studied the induction of CYP1A1 and GST$\alpha$, $\mu$, $\pi$ enzymes in Japanese monkey and rhesus monkey after the treatment with 3-methylcholanthrene (3MC) and di-n- butyl phthalate (DBP) and bisphenol A (BPA). The levels of mRNA were measured by RT-PCR in brain, intestine and liver. In the case of adult monkey, treatment with 3MC induced CYP1A1 mRNA in liver by 10-fold. The treatment with DBP induced CYP1A1 mRNA. Effects of 3MC and DBP on GST mRNA expression was not clear. But GST$\mu$ was slightly inhibited by the treatment with 3MC and DBP. GST$\pi$ was not induced by the treatment with 3MC and DBP in liver. GST$\alpha$ was slightly induced by the treatment with 3MC and DBP in liver. In the case of fetus monkey, the basal levels of fetus CYP1A1 mRNA and GSTs mRNA were relatively low compared to adult monkey. As the age of monkey increased, the basal levels of CYP1A1 mRNA were also increased. 3MC induced the expression of CYP1A1 mRNA in liver. The levels of GST$\mu$ and GST$\alpha$ were not changed by the treatment with 3MC and DBP. GST$\pi$ was slightly induced by the treatment with 3MC and DBP.

• 한국균학회지
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• 제30권2호
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• pp.124-130
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• 2002

본 연구에서는 버들송이(Agrocybe cylindracea)와 말똥진흙버섯(Phellinus igniarius)을 배양한 대두 추출물의 암예방 효과를 검토하기 위하여 in vitro상에서 암발생 억제물질 연구에 널리 이용되고 있는 기작 즉, Quinone reductase(QR), glutathione S-transerase(GST)의 활성 유도, glutathione(GSH)의 생성 촉진 그리고, polyamine 합성대사의 억제능을 측정하였다. 그 결과, 버들송이와 말똥진흙버섯를 배양한 대두 추출물이 마우스 hepatoma Hepa1c1c7 cell 배양에서 QR과 GST 유도활성이 있음이 확인되었다. 또한 GSH 생성량은 버들송이를 배양한 대두 추출물에서 20%, 말똥진흙버섯를 배양한 대두 추출물에서 40%로 증가하였다. 한편, 버들송이와 말똥진흙버섯을 배양한 대두 추출물의 polyamine 합성대사의 억제효과를 검토하기 위해 Acanthamoeba castellanii의 증식을 측정하였다. 그 결과, 버들송이와 말똥진흙버섯을 배양한 대두 추출물 20mg/3ml와 40mg/3ml를 처리할 경우 A. castellanii의 증식을 억제하는 것으로 나타났다. 이러한 결과 담자균을 배양한 대두 추출물은 in vitro상에서 나타난 암과 관련된 각종 활성으로부터 암예방 효과가 있는 것으로 나타나 기능성 식품으로서의 가능성을 보여주었다.

• 미생물학회지
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• 제33권2호
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• pp.86-91
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• 1997

Pseudomonas sp. DJ77로부터 클로닝된 glutathione S-transferase 유전자(phnC)의 염기서열을 결정하였다. 603bp의 open reading frame(ORF)이 존재하였고 개시코돈 앞에서 Shine-Dalgarno sequence를, 종결코돈 뒤에서는 terminator sequence를 발견하였다. phnC 유전자에서 만들어지는 phnC 단백질은 21,416 Da으로 SDS-polyacrylamide gel 전기영동 결과와 일치하였다. PhnC는 Bulkholderia cepacia LB400, Cycloclasticus oligotrophus RB1의 GST와 각각 53.7%, 49%의 높은 상동성을 나타냈다. 아미노산 서열의 상동성과 필수잔기들의 존재유무로 판단할 때 PhnC GST는 theta class GSTs와 진화적으로 유연관계가 높았지만 alpha, mu, pi, sigma class GSTs에서 구조적, 기능적으로 중요하다고 알려진 아미노산 잔기들이 PhnC GST에도 보존되어 있었다. 또한, phnC 유전자의 위치가 C. oligotrophus RB1, B. cepacia LB400 등의 GST 유전자 위치와 유사하다는 점에서 PhnC 효소는 난분해성 방향족 탄화수소의 분해에 관여하는 것으로 생각된다.

• Toxicological Research
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• 제23권2호
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• pp.127-133
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• 2007

Metformin is a drug used to lower blood sugar levels in patients with type 2 diabetes via activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK). The primary objective of this study was to investigate whether metformin at the pharmacologically effective concentrations affects the expressions of ${\gamma}$-glutamylcysteine synthetase and phase II antioxidant genes in the H4IIE cell. Treatment of the cells with either metformin or 5-aminoimidazole-4-carboxamide riboside (AICAR) abrogated tert-butylhydroxyquinone (t-BHQ) induction of ${\gamma}$-glutamylcysteine synthetase, a rate limiting enzyme of GSH synthesis. The ability of t-BHQ to induce glutathione S-transferases (GSTs), a major class of phase II detoxifying enzymes that playa critical role in protecting cells from oxidative stress or electrophiles, was also inhibited by the agents. Transcriptional gene repression by metformin was verified by the GSTA2 promoter luciferase assay. Moreover, either metformin or AICAR treatment significantly decreased t-BHQ-dependent induction of other GSTs (i.e., $GST{\mu}$ and $GST{\pi}$ forms). Taken together, our data indicate that metformin treatment may result in the repression of ${\gamma}$-glutamylcysteine synthetase and glutathione S-transferase genes possibly via AMPK activation.

• Journal of Yeungnam Medical Science
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• 제12권1호
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• pp.32-47
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• 1995

생쥐의 백혈병세포 L1210과 항암제에 대하여 내성이 유도된 L1210AdR, L1210VcR과 L1210Cis에서 glutathione의 농도와 glutathione의 합성 조절에 관여하는 ${\gamma}$-glutamylcysteine synthetase(GCS)와 ${\gamma}$-glutamyl transpeptidase (GGT), 세포 이물질을 축합하는데 촉매하는 glutathione S-transferase(GST)의 효소 활성도와 유전자의 발현 여부를 관찰하였다. 세포내 glutathione농도(${\mu}M/mg$ protein)는 L1210이 $0.41{\pm}0.003$, L1210AdR가 $0.73{\pm}0.006$, L1210VcR은 $1.16{\pm}0.060$, L1210Cis가 $2.19{\pm}0.282$으로 모세포에 비하여 내성세포에서 통계적으로 유의한 증가를 관찰하였다. Buthionine sulfoxamine(BSO)를 1 ${\mu}M$농도로 첨가하여 12시간 배양한 세포들에서의 glutathione농도는 L1210이 88%, L1210AdR가 85%, L1210VcR이 89%, 그리고 L1210Cis는 79%의 감소를 보였다. GCS의 활성도(nM/mg protein/min)는 L1210이 104인데 비하여 L1210AdR가 128, L1210VcR는 227, 및 L1210Cis는 212로 증가하였다. GGT의 활성도(nM/mg protein/min)는 L1210이 $2.15{\pm}0.531$이었고, L1210AdR은 $2.80{\pm}0.498$, L1210VcR은 $2.42{\pm}0.389$, 그리고 L1210Cis는 $2.98{\pm}0.623$으로 내성인 세포들에서 증가하였으며 L1210AdR과 L1210Cis에서 유의하였다. GST활성도(nM/mg protein/min)는 L1210이 $16.70{\pm}4.798$이었고, L1210AdR은 $14.51{\pm}3.402$, L1210VcR은 $19.52{\pm}4.255$, L1210Cis $17.77{\pm}4.495$로 L1210VcR과 L1210Cis가 약간의 증가를 보였으며, L1210AdR은 오히려 감소를 보였다. DNA의 slot blot에서 GCS, GGT, GST 유전자의 모세포와 내성세포간에 별다른 차이를 보이지 않았다. Northern hybridization에서 GCS는 약 4.5kb 크기의 band, GST-${\pi}$는 약 1.05kb 크기의 band를 보였으며 내성세포 모두에서 발현 증가가 관찰되었다. GGT의 경우 크기가 다른 6개의 band가 보였으며 특히 11.5 kb크기의 band에서 L1210AdR과 L1 210VcR의 발현이 증가하였으며, L1210VcR에서는 L1210과 다른 내성세포에서 보이는 1.95kb크기의 band가 보이지 않고 2.2kb 크기의 다른 band가 관찰되었다. 이상에서 L1210AdR과 L1210VcR의 내성에는 mdr1 유전자가 관여하고, L1210Cis의 내성에는 특히 glutathione이 중요하다. GCS, GGT 및 GST등의 활성도 및 유전자의 발현도 내성세포들에서 증가하였으며 이중 GCS는 내성세포내의 glutathione 합성에 가장 중요한 조절인자라 할 수 있다.

• Toxicological Research
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• 제17권
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• pp.251-256
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• 2001

The expression of phase II detoxifying enzymes is affected by a variety of compounds and the induction of the enzymes plays an essential role in chemoprevention. A variety of phytochemicals such as sulfur-containing chemoprotective agents (SCC) may trigger cellular signals and activate phase II gene expression through ARE activation. see induces glutathione S-transferases. Studies were conducted to investigate the role of mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-kinase (PI3-kinase) in the induction of GST (e.g. rGSTA2) by sec. We also studied the MAP kinase pathway responsible for the GST expression by see and compared that with the pathway activated by oxidative stress as a result of sulfur amino acids deprivation (SAAD). see inhibited phosphorylation of ERK1/2 although the effect of see on JNK and p38 MAP kinase was minimal. Wortmannin and LY294002. PI3-kinase inhibitors. abolished the increases in rGSTA2 mRNA and protein levels by SCC. Deprivation of cystine and methionine caused oxidative stress in H4IIE cells. as evidenced by a decrease in the reduced glutathione and an increase in prooxidant production. Electrophoretic mobility shift assay revealed that the ARE complex consisting of Nrf-1/2 and Maf proteins was activated 12~48 h. The rGSTA2 mRNA and protein levels were increased by SAAD. Activation of ARE and induction of rGSTA2 were both completely inhibited by PI3-kinase inhibitors. Inhibition of p38 MAP kinase by SB203580 prevented the ARE-mediated rGSTA2 induction. The results of this study showed that PI3-kinase might play an essential role in the ARE-mediated rGSTA2 induction by see or SAAD and that the dual MAP kinase pathways were responsible for the enzyme induction.